A labeler is known from DE 10 2008 007 890 A1 for applying labels in rows on a film sheet. In this, the labeler is arranged on a thermo-forming packaging machine downstream of a sealing station, and it can apply the labels from the top onto a cover film, or from below onto the bottom surface of a formed lower film of a pack. The film strip comprises a plurality of tracks and a plurality of rows of packs. A transfer device of the labeler picks up a number of labels from a label dispenser, while a lifting device of the transmission device is in a first position spaced from the film strip. The transfer device is subsequently moved by means of a travel device to the position where the number of labels picked up is to be applied onto the film strip.
The pneumatically operated lifting device then transfers the labels to the film strip and presses them on to the film strip, so that the labels remain securely adhered to the film strip. The film strip may be a lower film or a top film, and is hereinafter also referred to as the article strip. A vertical pressing position is adjusted by the duration which the pneumatic lifting device is supplied with compressed air. Additionally, the volume flow and thereby the lifting speed can be adjusted by means of a throttle.
The pressing force results from a target position of the lifting device and the position of the film strip onto which the labels are attached. Since the film strips are flexible in the direction of the pressing force, the flexibility together with the deflection of the film strips by the lifting device during the pressing process corresponds to the pressing force. Adjustment of the stroke and the target position, respectively, due to the changing environmental conditions is imprecise and inflexible for differing pack depths, since the volume flow, the duration and pressure applied by the pneumatic lifting device interact. By reducing the volume flow, the target position can be set with a little more accuracy using the duration of the supply of compressed air, but the slower lifting movement reduces the performance of the of the labeler. Fluctuating pressure in the supply line changes the lifting movement or the target position, respectively, without the operator or the machine controls being able to control these conditions.
When using spring-loaded pressing elements that press the labels onto the film strip, variations in the lifting movement or the target position, respectively, can be compensated. However, variations or improvements in an initial setting to accommodate for different pack depths does not currently exist.
During the movement of the transfer device by means of travel device on a thermo-forming packaging machine, security/safety clearances must be observed as this movement of the transfer device generates high kinetic energy and therefore correspondingly high security/safety clearances are to be observed. These high security/safety clearances require a corresponding high demand in physical space occupied by existing thermo-forming packaging machine of this construction.